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diff --git a/upstream/fedora-40/man3/mbrtowc.3 b/upstream/fedora-40/man3/mbrtowc.3 new file mode 100644 index 00000000..000d4564 --- /dev/null +++ b/upstream/fedora-40/man3/mbrtowc.3 @@ -0,0 +1,201 @@ +'\" t +.\" Copyright (c) Bruno Haible <haible@clisp.cons.org> +.\" +.\" SPDX-License-Identifier: GPL-2.0-or-later +.\" +.\" References consulted: +.\" GNU glibc-2 source code and manual +.\" Dinkumware C library reference http://www.dinkumware.com/ +.\" OpenGroup's Single UNIX specification +.\" http://www.UNIX-systems.org/online.html +.\" ISO/IEC 9899:1999 +.\" +.TH mbrtowc 3 2023-10-31 "Linux man-pages 6.06" +.SH NAME +mbrtowc \- convert a multibyte sequence to a wide character +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <wchar.h> +.P +.BI "size_t mbrtowc(wchar_t *restrict " pwc ", const char " s "[restrict ." n ], +.BI " size_t " n ", mbstate_t *restrict " ps ); +.fi +.SH DESCRIPTION +The main case for this function is when +.I s +is not NULL and +.I pwc +is +not NULL. +In this case, the +.BR mbrtowc () +function inspects at most +.I n +bytes of the multibyte string starting at +.IR s , +extracts the next complete +multibyte character, converts it to a wide character and stores it at +.IR *pwc . +It updates the shift state +.IR *ps . +If the converted wide +character is not L\[aq]\e0\[aq] (the null wide character), +it returns the number of bytes that were consumed +from +.IR s . +If the converted wide character is L\[aq]\e0\[aq], it resets the shift +state +.I *ps +to the initial state and returns 0. +.P +If the +.I n +bytes starting at +.I s +do not contain a complete multibyte +character, +.BR mbrtowc () +returns +.IR "(size_t)\ \-2" . +This can happen even if +.I n +>= +.IR MB_CUR_MAX , +if the multibyte string contains redundant shift +sequences. +.P +If the multibyte string starting at +.I s +contains an invalid multibyte +sequence before the next complete character, +.BR mbrtowc () +returns +.I (size_t)\ \-1 +and sets +.I errno +to +.BR EILSEQ . +In this case, +the effects on +.I *ps +are undefined. +.P +A different case is when +.I s +is not NULL but +.I pwc +is NULL. +In this case, the +.BR mbrtowc () +function behaves as above, except that it does not +store the converted wide character in memory. +.P +A third case is when +.I s +is NULL. +In this case, +.I pwc +and +.I n +are +ignored. +If the conversion state represented by +.I *ps +denotes an +incomplete multibyte character conversion, the +.BR mbrtowc () +function +returns +.IR "(size_t)\ \-1" , +sets +.I errno +to +.BR EILSEQ , +and +leaves +.I *ps +in an undefined state. +Otherwise, the +.BR mbrtowc () +function +puts +.I *ps +in the initial state and returns 0. +.P +In all of the above cases, if +.I ps +is NULL, a static anonymous +state known only to the +.BR mbrtowc () +function is used instead. +Otherwise, +.I *ps +must be a valid +.I mbstate_t +object. +An +.I mbstate_t +object +.I a +can be initialized to the initial state +by zeroing it, for example using +.P +.in +4n +.EX +memset(&a, 0, sizeof(a)); +.EE +.in +.SH RETURN VALUE +The +.BR mbrtowc () +function returns the number of bytes parsed from the +multibyte sequence starting at +.IR s , +if a non-L\[aq]\e0\[aq] wide character +was recognized. +It returns 0, if a L\[aq]\e0\[aq] wide character was recognized. +It returns +.I (size_t)\ \-1 +and sets +.I errno +to +.BR EILSEQ , +if an invalid multibyte sequence was +encountered. +It returns +.I "(size_t)\ \-2" +if it couldn't parse a complete multibyte +character, meaning that +.I n +should be increased. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR mbrtowc () +T} Thread safety MT-Unsafe race:mbrtowc/!ps +.TE +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +POSIX.1-2001, C99. +.SH NOTES +The behavior of +.BR mbrtowc () +depends on the +.B LC_CTYPE +category of the +current locale. +.SH SEE ALSO +.BR mbsinit (3), +.BR mbsrtowcs (3) |